[Serodiagnosis in the surveillance of the influenza virus circulation during the development of the pandemic caused by the A (H1N1)pdm09].

The goal of this work was to present the data of the study of the peculiarities of the generation factors of humoral immunity in the response to the infection with the pandemic influenza A (HIN1) pdmO9 in patients with different epidemiological anamnesis. High ability of the influenza viruses to spread over closed communities and the transfer of the maternal antibodies to babies, including a pandemic strain of the influenza virus A (H1N1) pdm09, was confirmed. The results of this study showed that the immune response to the surface antigens of the influenza virus (hemagglutinin and neuraminidase) was formed during the natural infection with the pandemic strains of the influenza A (H1N1) pdm09 in more than a half of the cases simultaneously.

Immune response after a single vaccination against 2009 influenza A H1N1 in USA: a preliminary report of two randomised controlled phase 2 trials.

BACKGROUND: Data are needed from large clinical trials of paediatric, adult, and elderly people to find the appropriate antigen dose and vaccination schedule for the 2009 pandemic influenza A H1N1. We therefore report preliminary safety and immunogenicity results after one injection of a licensed monovalent pandemic H1N1 vaccine in the USA. METHODS: We randomly assigned healthy children (aged 6-35 months and 3-9 years) and adults (18-64 years and >or=65 years) to vaccine containing per dose 7.5 microg (children and adults), 15 microg (children and adults), or 30 microg (adults only) haemagglutinin in two placebo-controlled, observer-masked, multicentre phase 2 studies done in the USA. Participants were allocated with an interactive voice-response system or computer-generated randomisation lists with opaque scratchable patches. Primary outcome was haemagglutination inhibition antibody response 21 days after the first of two planned vaccinations (interim analysis of studies in progress). Analyses were by full-analysis set. The trials are registered with ClinicalTrials.gov as NCT00953524 and NCT00952419. FINDINGS: 410 of 423 children and 724 of 750 adults given an active vaccine, and 50 of 51 children and 95 of 99 adults given placebo were assessed for immunogenicity on day 21. After active vaccination, 45 of 101 (45%; 95% CI 35-55) to 47 of 94 (50%; 40-61) infants aged 6-35 months, 75 of 109 (69%; 59-77) to 80 of 106 (75%; 66-83) 3-9-year-old children, 134 of 141 (95%; 90-98) to 144 of 144 (100%; 98-100) of 18-64-year-old adults, and 93 of 100 (93%; 86-96) to 93 of 98 (95%; 89-98) elderly adults were seroprotected (proportion with titres >or=1:40). No vaccine-related serious adverse events occurred. Injection-site and systemic reactions were reported by up to about 50% of every age and vaccine group, with no noticeable differences between vaccine and placebo groups. INTERPRETATION: One dose of vaccine was highly immunogenic in adults, suggesting that it afforded sufficient protection against this pandemic influenza A H1N1 virus. Two doses of vaccine will probably be needed in children younger than 9 years. Safety and reactogenicity of the vaccine were acceptable and similar to those of seasonal vaccine. FUNDING: Office of the Assistant Secretary for Preparedness and Response, and Biomedical Advanced Research and Development Authority.

[Investigation of prophylactic activity of Ingavirin, a new Russian drug, against grippe A virus (H3N2)].

Antiviral efficacy of Ingavirin was studied on albino mice infected intranasally by the grippe A virus (H3N2) vs. Tamiflu, Remantadin and Arbidol. Ingavirin used prophylactically in doses of 5 to 10 mg/kg was shown to be effective in protecting the animals from death and inhibiting the specific hemagglutinin formation and the virus reproduction in the lungs (by the accumulation).

Cranberry juice constituents affect influenza virus adhesion and infectivity.

Cranberry juice contains high molecular weight materials (NDM) that inhibit bacterial adhesion to host cells as well as the co-aggregation of many oral bacteria. Because of its broad-spectrum activity, we investigated NDM's potential for inhibiting influenza virus adhesion to cells, and subsequent infectivity. Hemagglutination (HA) of red blood cells (RBC) caused by representatives of both influenza virus A subtypes (H1N1)and H3N2) and the B type was inhibited by NDM at concentrations of 125 microg/ml or lower, which is at least 20-fold lower than that usually found in cranberry juice. A dose-response effect of NDM on HA was demonstrated. The infectivity of the A and B types was significantly reduced by preincubation with NDM (250 microg/ml), as reflected by the lack of cytopathic effect on Madine-Darby canine kidney (MDCK) cells and the lack of HA activity in the media of infected cells. The effect of NDM was also tested after A or B type viruses were allowed to adsorb to and penetrate the cells. Various levels of reduction in virus tissue culture infective dose TCID50 were observed. The effect was most pronounced when NDM was added several times to the infected MDCK cells. Our cumulative findings indicate that the inhibitory effect of NDM on influenza virus adhesion and infectivity may have a therapeutic potential.

Measles virus polypeptide-specific antibody profile in multiple sclerosis.

Elevated antibody (Ab) titers to measles virus (MV) is a frequent finding in MS. Although MV-Abs are synthesized intrathecally, it is not known whether this is due to polyclonal activation of B cells recruited from the blood, recognition of MV antigens within the CNS, or cross-reactivity with myelin antigens. This study examined these possibilities using purified MV polypeptides. We examined Ab reactivity to each polypeptide in serum and CSF from 21 MS patients, 5 with subacute sclerosing panencephalitis (SSPE), and 11 patients with other neurologic diseases (OND), and serum from 5 patients with acute MV infection and 11 normal controls. The serum of all subjects tested contained reactivity with MV and the 5 polypeptides. Of 21 MS patients, 20 had CSF reactivity with MV compared with 3/11 ONDs and 5/5 SSPE patients. Intrathecal MV-Ab synthesis was present in 11/21 MS patients, 5/5 SSPE, and in none of the ONDs. Nine of 21 MS patients had intrathecal synthesis of Ab to 2 MV polypeptides. Serum and CSF reactivity in MS patients was skewed towards the F polypeptide. The results are consistent with the concept of polyclonal B cell activation within the CNS, but the heightened response to F could also reflect cross-reactivity with a relevant antigen in MS.

Detection of measles virus genome directly from clinical samples by reverse transcriptase-polymerase chain reaction and genetic variability.

A simple and sensitive method for the detection of measles virus genome was developed, amplifying the regions encoding the nucleocapsid (N) protein and hemagglutinin (H) protein of measles virus by reverse transcriptase-polymerase chain reaction (RT-PCR). We examined a variety of measles patients: 28 patients with natural infection, 4 with measles encephalitis and 1 with subacute sclerosing panencephalitis (SSPE). In 28 patients with natural measles infection a single step PCR amplifying the N region resulted in a high detection rate for all plasma samples (28/28) within 3 days of the onset of rash and 80% (20/25) even on day 7 of the onset of rash and later. Within 3 days of the onset of rash, 24/25 (96.0%) of nasopharyngeal secretions (NPS) and 27/28 (96.4%) of peripheral blood mononuclear cells (PBMC) were positive for the N region PCR and the positivity rate of PCR decreased in NPS and PBMC after 7 days of the rash. In acute measles infection, measles genome was detected in all cell fractions, CD4, CD8, B cells, and monocytes/macrophages by the H gene nested PCR. Measles genome was also detected from cerebrospinal fluids (CSF) in patients with measles encephalitis, SSPE, and acute measles by the H gene nested PCR. PCR products of the N and H regions were sequenced and we confirmed the presence of measles genome. Based on the sequence data, chronological sequence differences were observed over the past 10 years. The sequences obtained from the SSPE patient were closely related to those of the wild viruses that were circulating at the time when the patient initially acquired measles. RT-PCR for NPS, PBMC, CSF, and plasma provides a useful method for the diagnosis of measles and molecular epidemiological study in addition to virus isolation.

Antimeasles immunoglobulin G in sera of patients with otosclerosis is lower than that in healthy people.

BACKGROUND: There is some evidence for an inflammatory process as a driving force in otosclerosis. Two popular hypotheses for the induction of this chronic inflammation have been proposed: an autoimmune phenomenon induced by an otic capsule specific antigen and measles virus infection. METHODS: Antibodies against measles virus hemagglutinin, polymerase, nucleocapsid, and matrix proteins were evaluated in sera from otosclerotic patients and in sera from healthy age-and sex-matched controls by use of the Western blot analyses. RESULTS: Significant differences were not detected between healthy men and women or between otosclerotic men and women. There were significantly stronger reactions against all viral proteins in the group of healthy women as compared with otosclerotic women despite a high standard deviation. The group of healthy male blood donors demonstrated significantly stronger reactions against polymerase and nucleocapsid proteins. Healthy blood donors again demonstrated stronger reaction compared with respective otosclerotic patients in a separate reaction for viral matrix protein. CONCLUSION: Our observation is consistent with viral participation in otosclerotic pathogenesis, but it is difficult to say if the diminished antimeasles humoral response is a consequence or the cause for a local measles infection. In light of the present data, we can discuss autoantibodies in otosclerosis as a sign of autoimmunity triggered by measles virus.

Occurrence and protective level of influenza infections using serology in patients with COPD in vaccination study.

OBJECTIVE: To investigate the prevalence, occurrence and protective level of influenza infections using serology in patients with chronic obstructive pulmonary disease (COPD) during a one-year influenza vaccination study. MATERIAL AND METHOD: A total of 123 patients with COPD were enrolled during the period of 1997 to 1998. There were 61 patients in the vaccine group and 62 patients in the placebo group with a mean age +/- SD of 67.6 +/- 8.0 and 69.1 +/- 7.5, respectively. The vaccine was composed of influenza A/Texas/36/91 (H1N1), A/Nanchang/933/95 (H3N2) and B/Harbin/07/94 strains. Antibodies to influenza viruses were detected by hemagglutination inhibition (HI) test using antigens of vaccine strains. RESULTS: The incidence of influenza proven by serological examination was 22/123 (17.9%) cases. Among 17/62 (27.4%) influenza cases in the placebo group representing natural infections, 3 (17.6%) were diagnosed as A (H1N1), 8 (47.1%) as A (H3N2), 3 (17.6%) as type A, 1 (5.9%) as type B and 2 (11.8%) as untypeable viruses. The 8.2% of influenza cases found in the vaccine group was significantly lower than 27.4% of that in the placebo group (Chi-square test, p = 0.01). The protection rate of influenza vaccination was 71%. Among 23 acute blood samples from 22 influenza cases, the titers ranged from < 10 to 20 corresponding to its type/subtype. In the vaccine group, 5 influenza cases occurred at 7, 7, 10, 11 and 11 months after vaccination. The HI antibodies to influenza A (H1N1), A (H3N2) and B viruses at titers of > or = 10 vs > or = 40 were 50.4% vs 21.9%, 54.5% vs 28.5% and 17.9% vs 4.1%, respectively. CONCLUSION: The findings indicated that from 1997 to 1998, the occurrence of influenza as natural infection was 27.4%. Influenza A (H3N2) was more frequently prevalent than A (H1N1) and B viruses. The influenza vaccination in COPD patients was effective. The protective HI antibody titers were > or = 40. The patients without protective HI antibody to A (H1N1), A (H3N2) and B viruses were 78.1%, 71.5% and 95.9%, respectively. Such patients were considered to be at high-risk for influenza and recommended to have vaccination.

[Laboratory diagnosis of dengue virus infections in Aragua State, Venezuela: October 1997-December 1998]. / Diagnóstico de laboratorio de infecciones por el virus dengue en el estado Aragua; Venezuela: Octubre 1997-Diciembre 1998.

The efficacy of a proactive dengue surveillance system to predict epidemics depends on the laboratory diagnostic capacity for an early detection of virus circulation. This study shows the results of the dengue virologic and serologic surveillance accomplished in Aragua State (Venezuela) from October 1997 to December 1998. Five hundred and forty seven sera from suspected dengue patients were tested using the techniques of Virus Isolation and Immunofluorescence Serotyping (VIIS), Reverse Transcriptase-Polymerase Chain Reaction (RT-PCR), Anti-dengue IgM Capture Enzyme Immunoassay (MAC-ELISA) and Haemagglutination Inhibition test (HI). Of the tested sera, 97.4% resulted positive to at least one technique; of these, 60.4% were classified as confirmed cases (virologically positives) and 39.6% as probable cases (virologically negatives/serologically positives). Though the majority of positive cases occurred during the 1997 and 1998 epidemic periods, the gradual increase of the seropositive rates between both periods suggested the incoming 1998 outbreak. Den-1 (51.2%), Den-2 (37.9%) and Den-4 (10.6%) infected patients were detected as well as one dual infection of Den-2 and Den-4 (0.3%). Dengue hyperendemicity (co-circulation of Den-1, Den-2 and Den-4) in Aragua State was confirmed together with the detection of few cases (6.5%) of Dengue Hemorrhagic Fever/Dengue Shock Syndrome cases (HF/DSS); 38.1% of these cases occurred in patients with secondary infections. The high percentage (85.7%) of DHF/DSS cases infected by Den-2 virus supports the reported virulence of this serotype.

[The antigenic structure of influenza B viruses isolated in 1991]. / Antigennaia struktura virusov grippa B, vydelennykh v 1991 g.

A comparative immunological analysis of the antigenic structure of reference influenza B viruses of 1940-1984 and isolates of 1986-1991 using monospecific antibodies to individual antigenic determinants and monoclonal antibodies to hemagglutinin of B/Oregon/5/80 virus demonstrated a further antigenic drift of influenza B viruses from the reference variants B/Victoria/2/87 and B/Yamagata/16/88. Alongside with circulation of viruses with new antigenic properties, variants were found in the epidemic outbreak of 1991 whose hemagglutinin had common antigenic markers with those of variants of the previous years.

[The detection of the antigens of influenza viruses A and B in the blood of healthy donors]. / Obnaruzhenie antigenov virusov grippa A i B v krovi zdorovykh donorov.

Blood clots and sera were obtained from donors at a Moscow city transfusion clinic during 1984-1988 and tested by indirect solid-phase enzyme immunoassay with original test-sera to hemagglutinating antigens of influenza A (H1 and H3) and B viruses. Examinations of 1714 blood samples demonstrated hemagglutinating antigens of different specificity (from 0.8% to 35%), the detection rate of one or another antigen correlating with the epidemic activity of influenza virus serovariants A and B. The virus-specific antigens, however, were almost regularly detected in the blood of healthy subjects in the interepidemic seasons as well. The highest number of positive results was observed in tests with blood clot or serum. The results indicate the principal capacity of influenza virus to persist in apparently normal subjects.

[The dependence of determining the hemagglutinin content by SRID on the test system used and on the detergent]. / Zavisimost' opredeleniia soderzhaniia gemaggliutinina metodom ORID ot ispol'zuemoi test-sistemy i detergents.

The assay systems for single radial immunodiffusion (SRD) represented by standard reagents of antigens and monospecific antisera to A and B influenza virus haemagglutinin and prepared in two different countries were used for elucidation of the influence of monospecific antisera and some ionic and nonionic detergents on the determination of hemagglutinin content in the homologous (antigen and antiserum from the same country) and heterologous (antigen and antiserum from different countries) assay systems. A high specificity of SRD reaction excluding substitution of antiserum from one country for analogous preparation from another as well as detergent interchangeability were shown.

[Yucaipa-like viruses isolated in Kazakhstan in 1987-1989]. / Izuchenie iukeipapodobnykh virusov, vydelennykh v Kazakhstane v 1987--1989 gg.

From domestic birds 13 strains of avian paramyxoviruses, serotype 1, and 14 strains of serotype 2 were isolated. Avian paramyxoviruses, serotype 2, differ antigenically and biologically from each other and from the prototype variant chicken/Yucaipa/California/56. The virus was also detected experimentally in birds having contact with the infected specimens. Examinations of avian blood sera revealed wide dissemination of viruses related to the chicken/Yucaipa/56 strain in domestic bird breeding farms (43.6% to 50.0% of positive birds). The detected variability of the antigenic structure of the isolates attests to the potential emergence of a pathogenic variant.

[The antigens and nucleotide sequences of influenza A and B viruses in the lymphocytes of human peripheral blood]. / Antigeny i nukleotidnye posledovatel'nosti virusov grippa A i B v limfotsitakh perifericheskoi krovi cheloveka.

Markers of influenza A and B viruses (antigens of hemagglutinin and specific nucleotide sequences) were detected in lymphocyte preparations from normal subjects. The rate of detection of the antigens and specificity (type and subtype appurtenance) of the markers correlated with the influenza epidemic situation. Lower titers of antibodies to the virus whose antigens were present in lymphocytes were observed.

[The incidence of detecting influenza virus antigens in the peripheral blood lymphocytes of donors in relation to the epidemic activity of influenza viruses A and B]. / Chastota vyiavleniia antigenov virusov grippa v limfotsitakh perifericheskoi krovi donorov v zavisimosti ot épidemicheskoi aktivnosti virusov grippa A i B.

Antigens of influenza A and B viruses in the peripheral blood lymphocytes of normal human subjects are found regularly both in epidemic and interepidemic periods. The level of detection of viral proteins in lymphocytes varies widely and correlates with the epidemic activity of the viruses. Influenza virus antigens were found several months before a rise in the incidence of the disease, the per cent ratio of the identified antigens correlating with the pattern of antigen detection in nasopharyngeal washings during an epidemic outbreak. Most frequently, the antigen found in lymphocytes was that of the main etiological agent of a definite epidemic; less frequently the hemagglutinin of the virus accompanying the one dominant in a given epidemic was found.

Simple haemadherence test for the detection of class-specific immunoglobulins to hepatitis A virus.

The ability of hepatitis A virus (HAV) to agglutinate human erythrocytes was used to develop IgM and IgG antibody capture haemadherence tests (MACHAT and GACHAT). Haemadherence was dependent on the pH of the red cell suspension and was best in the pH range 5.4 to 5.8. The tests were applied to serum, urine, and saliva specimens from individuals susceptible to, or with recent or past infection with HAV. Haemadherence test reactivities were compared with results obtained with IgM and IgG antibody capture radioimmunoassay (MACRIA and GACRIA) and competitive radioimmunoassay (COMPRIA). For 339 serum specimens examined, the sensitivity and specificity of MACHAT were 98.2% and 99.6%, respectively, and of GACHAT 99.1% and 100.0%. For 303 urine specimens, the sensitivity and specificity of MACHAT were 99.1% and 100.0%, and of GACHAT 100% for both. On initial testing, accuracy on saliva specimens was considerably less. For 2,819 saliva specimens, the sensitivity and specificity of MACHAT were 85.7% and 97.2% and of GACHAT 90.4% and 94.7%. The haemadherence test is a simple, inexpensive method which is satisfactory for use on serum and urine specimens. MACHAT and GACHAT can be used for epidemiological investigations, e.g., hepatitis A outbreaks and, in conjunction with a confirmatory test, for clinical diagnostic testing.

B lymphocyte hyperactivity in families of patients with systemic lupus erythematosus.

Blood cells spontaneously secreting IgG and IgM and the level of plasma immunoglobulins and antibodies to dsDNA, ssDNA and influenza virus haemagglutinin have been determined in families of patients with SLE, in 'normal' families and groups of 'normal' individuals. IgM values were consistently higher in females than in males. About one in three of healthy blood relatives gave values in excess of the sex-matched control range in one or more of these test, particularly notable being raised values of IgG anti-dsDNA and total IgG shown by female relatives. High-scoring relatives were more likely to be offspring or parents than siblings of patients, suggesting, together with evidence from a spouse group, the involvement of environmental as well as genetic factors in these families. Correlation analysis between the various assays in the different groups showed a clear distinction between the female control group, where there were no associations, and the female relative group where there were strong associations, including a significant correlation between IgM and IgG antibodies to dsDNA. The male groups produced a more variable picture but the patients gave a remarkably consistent pattern of moderate positive associations. Pokeweed mitogen induced a higher level of IgG production in blood cells of relatives than in controls. These findings are suggestive of a breakdown in relatives of normal antibody regulation. Investigation of immunological abnormalities in family members provides a powerful tool for the analysis of a complex disease.

Infection of children with avian-human reassortant influenza virus from pigs in Europe.

Pigs have been proposed to act as the intermediate hosts in the generation of pandemic human influenza strains by reassortment of genes from avian and human influenza virus strains. The circulation of avian-like H1N1 influenza viruses in European pigs since 1979 and the detection of human-avian reassortants in pigs raises the question of whether these viruses actually have the potential to transmit and cause disease in humans. We now report the serologic and genetic characterization of two human influenza A viruses (A/Netherlands/5/93 [H3N2] and A/Netherlands/35/93 [H3N2]) that caused influenza in children in The Netherlands in 1993. The results show that these viruses are human-avian ressortants that were generated and currently still are circulating in European swine. This shows the pivotal role that pigs can play in the generation and transmission of avian influenza virus genes to humans and their potential to generate a new human pandemic strain.